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Node.js - PostgreSQL - select first N rows
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In this article, we would like to show you how to select the first N rows in the PostgreSQL database using Node.js.
Note: at the end of this article you can find database preparation SQL queries.
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const { Client } = require('pg');2
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const client = new Client({4
host: '127.0.0.1',5
user: 'postgres',6
database: 'database_name',7
password: 'password',8
port: 5432,9
});10
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const fetchUsers = async (count) => {12
try {13
await client.connect(); // gets connection14
const { rows } = await client.query('SELECT * FROM "users" LIMIT $1', [count]);15
console.table(rows);16
} catch (error) {17
console.error(error.stack);18
} finally {19
await client.end(); // closes connection20
}21
};22
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fetchUsers(3); // fetch first 3 rowsResult:
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┌─────────┬────┬─────────┬───────────────────┬──────────┐2
│ (index) │ id │ name │ email │ country │3
├─────────┼────┼─────────┼───────────────────┼──────────┤4
│ 0 │ 1 │ 'Tom' │ 'tom@email.com' │ 'Poland' │5
│ 1 │ 2 │ 'Chris' │ 'chris@email.com' │ 'Spain' │6
│ 2 │ 3 │ 'Jack' │ 'jack@email.com' │ 'Spain' │7
└─────────┴────┴─────────┴───────────────────┴──────────┘create_tables.sql file:
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CREATE TABLE "users" (2
"id" SERIAL,3
"name" VARCHAR(100) NOT NULL,4
"email" VARCHAR(100) NOT NULL,5
"country" VARCHAR(15) NOT NULL,6
PRIMARY KEY ("id")7
);insert_data.sql file:
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INSERT INTO "users"2
("name", "email", "country")3
VALUES4
('Tom', 'tom@email.com', 'Poland'),5
('Chris', 'chris@email.com', 'Spain'),6
('Jack', 'jack@email.com', 'Spain'),7
('Kim', 'kim@email.com', 'Vietnam'),8
('Marco', 'marco@email.com', 'Italy'),9
('Kate', 'kate@email.com', 'Spain'),10
('Nam', 'nam@email.com', 'Vietnam');Native SQL query (used in the above example):
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SELECT * 2
FROM "users" 3
LIMIT 3 -- LIMIT N